Attached Files:

I've never had that problem, but I do use gimp, so here are the settings I'd use for saving a kerb texture:
Compression: DXT1
Generate mipmaps: True
Advanced: Mipmap filter: Nearest (helps when the texture can be seen from afar).

Does your material use bump and/or specular maps? Are they scaled differently to the diffuse map? I can't think of anything else - perhaps you could provide more info?